Table top



March 12, 1940. B T EL R 2,193,018!

TABLE TOP Filed June 25, 1938 Patented Mar. 12,1940,

UNITED STATES PATENT OFFICE 2,193,013 v TABLE 'ror Clements Batcheller,Glens Falls, N. Y., assignor to Allegheny Ludlum Steel Corporation,acorporation of Pennsylvania Application June 25,-1938, Serial No.215,834

My invention generally relates to table tops and,

particularly, to a structure formed of a laminated, composite productand to the method of forming the same which structure is primarilyadapted for 6 use as table tops.

Ordinarily, sink units are deepstamped from comparatively heavy gaugemetal sheets whereby to form a depressed sink, surrounded by asubstantially flat metal plate which serves as a table top. These may beformed from a sheet or plate v of corrosion resistant, alloy steel orMonel metal but the use thereof is quite limited due mainly to the factthat the amount of metal necessary to provide adequate structuralstrength with a mini- 5 mum of buckling or distortion renders the costof such units, so far as the cost of metal is concerned, very high.Moreover, such stamped metal sink units are objectionable because of thesharp metallic note or ring which is produced when struck and thiscondition has obtained even though measures have been taken to preventit. Of course, the high cost of stamped, heavy gauge,

' metal sink units with table tops is not due entirely to the cost ofmetal alone, as above indicated, but is also dependent upon die costsand labor entailed in forming the sinks and also losses encountered dueto defective products.

Metals in sheet or strip form, when employed in forming table tops suchas those used with sinks and for cabinets and the like are ordinarily ofabouta 20 or 24-gauge thickness. Sheets of corrosion resistant, alloysteels of this gauge, though admirably suited for the purpose, are ofsomewhat greater weight than, for example, like sheets of and they maybe quite easily dented or otherwise distorted when subjected to animpact force.

It is, therefore, a first object of my invention to provide a table topparticularly adapted for uses such as those above pointed out and formedof a composite product comprising a surface element of corrosionresistant metal and preferably a corrosionreslstant alloy steel, saidproductbe- 4 ing characterized by the facts that, due to theconstruction employed, it is inherently of sufllcient structuralstrength for adaptation to the uses contemplated and the corrosionresistant "surface thereof is much less susceptible to dent ing ordistortion than a sheet of corrosion re-.

sistant, alloysteel of the gauge ordinarily employed for such purposes.

Other objects of my invention reside in the provisionof a table topparticularly designed for use with sinks; in providing a compositeproduct of composited elements ordinary carbon steel, their cost is muchgreater the character above pointed out and in the method of forming atable top therefrom.

With these and other objects in view, my invention includes the novelconstructions and those steps in the method of forming table topsdescribed below and illustrated in the accompanying drawing, in which-Fig. 1 is a magnified, fragmentary sectional view throughthecomposite-product of my invention; 7 X I Fig; 2 isa. plan viewillustrating the preformed, employed in making my table top: A

Fig. 3 is a fragmentary'sectional view, somewhat enlarged, taken inabout the plane 3-4 of g. 2 and illustrating a partially formed table inpreforming the molded sheet element of my composite product; 1 I

Fig. 5 is a fragmentary, sectional elevation view illustrating themethod of preforming the molded sheet element;

Fig. 4 is a plan view of a press plate employed In the following,although I have referred to a 35 table top construction particularlyintended to form a table top for a sink, it is to be understood that theterm "table top is intended to include table and cabinet tops, cabinetpanels, table tops with splash hacks for sinks and like elements.

I have discovered that light gauge sheets of corrosion resistant metalsand, particularly, sheets of corrosion resistant alloy steel, preferablythose coming within the ranges ofso-called stainless steels, whencomposited to a comparatively heavy gauge sheet of carbon steel, areparticularly adapted for use in fabricating table tops for the purposesherein contemplated.

Under cold rolling processes,- corrosion resistant;

alloy steels may be produced in strip form in 50 thicknessesof the orderof about from 0.004" to about 0.010" or 0.011". These strips are usuallyformed in widths of about 27" or 28" and in lengths of about'500 feet orgreater. Taken alone, these strip products,- although desirable becausesives'of the ordinary type require the presence of air to enable thesolvent therein contained to of. their enduring qualities, lightness inweight per unit of area and lustrous surface appearance, are limited inthe uses to which they may be put mainly because of lack of suficientstructural strength.

However, when a corrosion resistant, alloy steel sheet or strip productof the foregoing character is composited to a sheet of ordinarycarbonsteel, in the aggregate forming a composite sheet of, for example, about20 to 24-gauge thickness, the corrosion resistant surface thereof isharder than that of a like gauge, corrosion resistant, alloy steel sheetand cannot be so'easily dented or deformed. When a composite metal sheetproduct of the foregoing character was subjected to Rockwell tests, itshowed a corrosion resistant surface hardness which was considerablygreater than that of a specimen of corrosion resistant, alloy steel of athickness substantially equal to that of the composite product.

Furthermore, a composite sheet product of the foregoing character ismuch'lighterin weight than an equivalent sheet of corrosion resistantalloy steel and the cost thereof is considerably lower.

However, for the purposes herein contemplated, the composited corrosionresistant and carbon, steel sheets should be adequately reinforced, ashereinafter pointed out, and a table top formed of the resulting,composite product will be found to be particularly adapted for thepurposes herein set forth because, among other things, of itsdurability, structural strength, lightness in weight, resistance todenting or deformation due either to impact or the presence of moistureand low cost. It is also characterized by the practical absence ofmetallic sound or ring when struck.

In forming the composite product of which my table top is fabricated, Iprefer first to comp site the thin, corrosion resistant, alloy steelsheet, which may be of a thickness ofthe order hereinabove pointed out,with a carbon steel sheet, which may be of a thickness of about 0.016"and, thereafter, said metal sheets are secured to a molded sheetproduct. In order to secure the metal sheets together and effect astrong bond therebetween, one surface of the carbon steel sheet I (seeFig. 1) is first galvanized as indicated at 2 and the galvanizedsurfaceis then treated to render it roughened or rugose whereby to aid to aconsiderable extent in eflecting an extremely strong bond between thecarbon steel sheet I and the thin sheet 3 of corrosion resisting, alloysteel.

To' roughen a'galvanized surface, it may be subjected, for example, to asand blast or pickled in sulphuric acid or, of course,other means may beresorted to in order to provide the desired roughness of the galvanizedsurface. The surface of the corrosion resistant, alloy steel sheet isalso preferably roughened and'the roughened surfaces of the two metalsheets are then placed together with a. suitable adhesive therebetweenfor boridin'gpurposes, I

Due to the fact, that the two metal elements when placed together-andsubjected to pressure, do not permit the ingress of air therebetween, anadhesive, which may be termed a thermo plastic resin, should'be employedbecause adheevaporate and produce congelation. The ther moplastic resin,which I prefer to employ, is one which, when applied as a liquid in afilm to the roughened surface of both metal elements and permitted todry, becomes substantially non tacky at ordinary temperatures butbecomes adhesive when subjected to heat and pressure, or,

pressure alone, when of suflicient magnitude.

A suitable adhesive having the foregoing properties is one which maycomprise as essential ingredients nitrocellulose, a synthetic resin andat least one solvent, and the synthetic resin is preferably presenttherein in such proportion that a film of the adhesive when dry issubstantially non-tacky at ordinary temperatures or even slightlyelevated temperatures but is adhesive under pressure and heat or under acomparatively high pressure alone. An adhesive of this character is alsomoisture or water proof and is not susceptible to oxidation but is quitedurable. Furthermore, it has high dielectric properties therebypreventing electrolytic decomposition of the metals,

In compositing the carbon steel and corrosion resistant, alloy steelsheets together, a film of thermoplastic resin of the foregoingcharacter is applied to the roughened surfaces of each sheet element andpermitted to dry and, thereafter, said elements are superposed with thedried film 6 of thermoplastic resin therebetween and subjected to heatand pressure whereby to effect an extremely strong bond therebetween;For exam- 'ple, the superposed sheets may be placed in a hydraulichot-plate press and subjected to a pressure of about 50 pounds persquare inch under a temperature of from about 300 to about 550 F. for aperiod of about 8 minutes.

In accordance with my invention, the composited, metal sheets aresecurely bonded to a sheet of a hard, stone-like, molded product, in-.dicated at 5 in Fig. 1.3 I

' The molded sheet produce which I prefer to use is preferably anasbestos fibre board or panel.

which comprises principally asbestos fibres and a cementing agent. Forexample, the molded sheet produce may comprise the following:

Short asbestos fibres (waste fibres) pounds 200 Calcined magnesite (200mesh) do 40 Bentonite (colloidal clay, 200 mesh) do 12 Water toplasticize gallons 20 A typical formula of another example of asuitable, molded sheet product is as follows:

Water for workability.

A molded product of the type represented by the above formulae ischaracterized by its comparatively great strength and toughness and bythe fact that, even when very thin, it shows no tendency to warp orbuckle when moist or wet.

Furthermore, it may be molded orrolled to provide a smooth surface andthe product may be easily worked, if desired, as by sawing, grinding,

my composite product but a board or sheet of the character-pointed outis very desirable because of its properties which render it ofparticular value in forming a composite product which is primarily.designed for the fabrication of table topsas herein indicated. 2 Inbonding the molded sheet, which preferably isofathickness of about%"butnot less than W, 78

' I and the marginal lips sistant, alloy steel sheet to the compositedmetal sheets-and to the back of the carbon steel sheet, I prefer toemploy a thermoplastic resin of the character above pointed out which isapplied as a liquid in a fllm to the surface of the carbon steel sheetand the molded sheet, permitted to dry and then, by superposing thesheet elements with the dried, film of adhesive 4' therebetween andsubjecting said elements to heat and pressure substantially in themanner hereinbefore set forth, a strongly bonded, composite product isproduced.

In forming a table top from my composite product, the respectiveelements thereof, in accordance with my invention, are preformed beforebeing composited as illustrated by way of example in the drawing. Thecarbon steel sheet I is formed substantially to conform with thedimensions of the finished table top as repreented by the dotted linesSin Fig. 2. The corrosion resistant, alloy steel sheet 3 is blanked outto provide lips I which are adapted to extend beyond the carbon steelsheet and on each side thereof whereby ultimately to form, ,in part,

flanges along the sides of the table top. The

molded sheet is also preformed substantially to conform to theconfiguration of the corrosion resistant, alloy steel sheet 3.

In forming asbestos sheet or board products, they are usually removed intheir'plastic, formative stage as sheet mats and placed upon relativelyheavy gauge, steel press plates having a very smooth, oil-filmlubricated surface. Several of these press plates with their respectiveplastic mats are stacked one upon the other and, under pressure, areallowed to remain in the stack until suiliciently hydrated to permitstripping from the press plates. In prefor'ming the molded sheet productbefore combining it with the metal elements, I employ a presspplate,indicated at 8, which is provided with V-shaped elements 9 extendinglongitudinally of the plate and similar 'v-shaped elements III whichextend transversely of the plate, these elements intersecting in zonesadjacent. the corners of the press plate. The V-shaped elements9 and IDare. arranged to form intersecting grooves in the finished, moldedproduct which extend entirely across and lengthwise. thereof and whichwhen said sheet is positioned beneath the carbon steel sheet I will liesubstantially beneath the transverse and longitudinal edges thereof. Theplastic mats may be placed upon press plates 8, stacked and pressed inthe ordinary manner and, when finished, will contain the grooves II, thesides of which are preferably arrangedsubstantially at right angles toeach other or slightly in excess thereof and with the apex close tobutslightly spaced below the top of the molded sheet whereby the endportions l2, which may extend on all sides of,the sheet, may be bentdownwardly to form flanges. 4 After the molded sheet has become hardenedthe corners thereof indicated in dotted lines at l3 Fig. 6' may bebroken out as illustrated so that the finished, molded sheet thenconforms substantially in configuration to the corrosion resistant,

alloy steel sheet 3. When, of course, the elements are placedin'superposed position and properly aligned, as illustrated in Fig. 2,the grooves II will underlie the edges of the carbbn steel sheet 1 ofthe corrosionuemetal sheets I and 3, being first secured together asabove indicated, and in properly'aligned relationship, are then alignedwith and superposed will overlie themarginal Q portions l2 ofthe moldedsheet product. The

3 upon the molded sheet product I and secured thereto as aboveindicated, the marginal lips I being thereby bonded directly to themarginal portions I! of the molded sheet as illustrated in Fig. 3.Thereafter, of course, the marginal portions may be bent down asillustrated in Fig. 7 to provide a table top with flanged sides abuttingeach other at the ends thereof. Suitable means, of course, or anadhesive may be provided to prevent relative movement between the tabletop and the flanged sides thereof and theends of the metal facing of thesides may be soldered or otherwise secured together.

Where the table top is to be employed as a table top for sinks, therespective, composited elementsl, 3 and 5 are preformed with openingstherein which, when the elements are arranged in superposed positions asillustrated, are adapted substantially to register with each other. Theopening I 4 in the molded sheet 5 and the opening IS in the carbon steelsheet I may be of substantially like size but the opening IS in thecorrosion resistant, alloy steel sheet 3 is preferably of substantiallylike configuration but somewhat smaller than openings l4 and i5 wherebyto provide an inwardly extending flange ll. After or during compositionof the elements, flange l1 may be depressed to form a ledge I8 extendingabout the opening in the composite product which is preferably slightlyspaced below the upper surface'of the table top and to an extentsuflicient to permit a flanged sink element l9 to be supported thereonwith the rim of said sink substantially flush with the upper surface ofthe table top. The sink, of course, may be soldered or otherwise securedto the element 3 and, in appearance, will closely resemble an integralsink and tabletop construction.

In forming the opening M in the molded sheet 5, I prefer, in theformative stages of the product, to form a frangible sectionsubstantially in the same manner employed in forming the grooves H whichsection, when removed from the sheet, will provide the opening M. Thisis preferably accomplished by providing an annular element 20 whichconforms in size and shape to the opening l4 and which is accuratelypositioned upper edge thereof arranged to penetrate the plastic matsubstantially to but short of the upper surface thereof. 'Cif course,when the molded product has been removed from the press I and mountedupon the press plate 8 with the splash back or upstanding flangetherefor may be formed which, in widtli including the width= or heightof the splash back is in excess of that of the corrosion resistant,alloy steel strip employed. For example; assuming e 27" wide, corrosionresistant, alloy steel strip is provided and it is desirable to form atable top substantially 24" in width provided with a downwardly flangededge on one side and on the opposite side with an upstanding splashback, for example, about 6" in width or height, it isnecessary tocombine two corrosion resistant, alloy steel sheets and, in so doing, itis desirable that the zone in which they are joined together is renderedsubstantially imperceivablaf vA construction af-. fordingflthis desiredresult is attained by overfolding the marginal portions of .a-flrstcorrosion resistant, alloy steel sheet 3 with the marginal portion of asecond sheet 25 as illustrated at til in Figs. 3 and 9 and arranging theoverfolded portions thereof, when composited with a carbcn steel sheetand molded sheet product asupwardly within the molded sheet as butterminates slightly below the upper surface thereof whereby the marginalportion 2% of the sheet 23 may be bent upwardly as illustrated in Fig. 9to provide a splash back for the table top and the corrosion resistantsurface of the table top and splash back will appear as substantiallyintegral surfaces.

From the foregoing, it should be apparent that by preforming the moldedsheet product in the manner herein described supplemental Work such asgrooving the back thereof and cutting out openings therein such as thatadapted to receive the sink are eliminated and it is merely necessary toremove predesigned portions thereof before compositing with the metalsheet elements. Thereafter, of course, it is merely necessary to benddown the marginal portions to prothe dimensions of the upper surface ofthe table.

top, those zones of the metal sheets or laminae which are bondedtogether are not subjected to a flanging operation thereby precludingthe production of stresses which may tend to impair the bondtherebetween.

It is to be understood that though I have referred to a corrosionresistant, alloy steel sheet and preferably to an alloy steel comingwithin the ranges of so-called stainless steels as the preferred facingelement of my composite product, I may employ other corrosion resistantmetals and it is to be further understood that by the term carbon steel,I intend to include low carbon irons.

The term sheets as herein employed as descriptive of the respectivelaminae of my composite product is intended-to include units of plate orstrip dimensions; and by the term soldered, I meanxto include welded orother like manners of joining the elements together. v

What I claim is: I

1. A table top formed of a composite product comprising a. carbon steelsheet of comparatively heavy gauge having secured to one side thereof acomparatively light gauge sheet of corrosion resistant metal'and havingsecured to the other side thereof a hard, molded sheet productcomprising prin'cipally asbestos fibre and a cementing agent.

2. A table top formed of a composite product comprising a carbon steelsheet of comparatively heavy gauge, a sheet of comparatively lightgauge, corrosion resistant metal and a molded sheet product comprisingprincipally asbestos fibre and a cementing agent, said corrosionresistant and molded sheets being secured to and on opposite sides ofsaid carbon steel sheet by a layer of thermoplastic resin.

3. A table top formed of a composite sheet roduct comprising a lamina ofcarbon steel of comparatively heavy gauge having one surface thereofgalvanized, a lamina of corrosion resistant metai secured thereto, and alamina comprising a hard, molded sheet product comprising principallyasbestos fibre and a cementing agent secured to the other surface ofsaid carbon steel lamina; said laminae being secured together by a layerof thermoplastic resin.

4-. A table top formed of a composite sheet product comprising a laminaof carbon steel of comparatively heavy gauge having one surface thereofgalvanized, a lamina of corrosion resistant, alloy steel securedthereto, and alarmina comprising a hard, molded sheet product comprisingprincipally asbestos fibre and a cementing agent secured to the othersurface of said carbon steel lamina; said laminae being secured togetherby a layer of thermoplastic resin.

5. A flanged table top comprising laminae of comparatively light gauge,corrosion resistant metal, comparatively heavy gauge carbon steel and amolded sheet product comprising principally asbestos fibre and acementing agent, said laminae being secured together by a layer ofthermoplastic resin with said carbon steel as a core element and saidflanged sides comprising laminae only of said corrosion resistant metaland i said molded sheet product Isecured together.

6. A flanged table top comprising laminae of comparatively light gauge,corrosion resistant metal, comparatively heavy gauge carbon steel and amolded sheet product comprising principally asbestos fibre and acementing agent, said laminae being secured together by a. layer ofthermoplastic resin with said carbon steel as a core element; and saidelement being provided with an opening therein adapted to receive a sinkof substantially like configuration.

7. A flanged table top comprising laminae of comparatively light gauge,corrosion resistant metal, comparatively heavy gauge carbon steel and amolded sheet product comprising principally asbestos fibre and acementing agent, said laminae being secured together by a layer ofthermoplastic resin with said carbon steel as a core element; and saidtable top being provided with an opening therein but the opening in saidcorrosion resistant lamina being somewhat smaller than that in saidcarbon steel lamina and the edges thereof being slightly depressed toform a peripheral flange adapted to support a sink within the opening ofsaid table top.

8. A flanged table top comprising laminae of comparatively light gauge,corrosion resistant metal, comparatively heavy gauge carbon steel and amolded sheet product comprising principally asbestos fibre and acementing agent, said laminae being secured together by a layer ofthermoplastic resin with said carbon steel as a core element; and thelaminae of said table top being provided with substantially registeringopenings,

spaced from the sides thereof, but the opening in said corrosionresistant lamina being somewhat smaller than that in the other laminaeand the edges thereof being slightlydepressed whereby to form aperipheral flange adapted to proagent, a sheet of comparatively heavygauge carbon steel superposed on said molded sheet and secured theretowith said molded sheet extending therebeyond on opposite sides, twosheets of comparatively light gauge corrosion resistant metal arrangedin side by side relation but with adja cent edges overfolded and securedtogether, one

of said latter sheets being secured to said carbon steel sheet with saidoverfolded portions adja- 10 cent one edge thereof and with portions ofsaid sheets overlying and being secured to those portions ofsaid moldedsheet which extend beyond said carbon steel sheet, the under side ofsaid molded sheet being grooved substantially beneath the edges of saidcarbon steel sheet whereby to permit bending of said sheet on one sideto provide a downwardly extending flange and on the other side in thezone of the overfolded sheets to provide an upwardly extending flange.

CLEMENTS BATCHELLER. 10

